Growing Plants Under Lights the Easy Way

What do keen gardeners do when the weather's bad? Well, we can sit at home and do some forward planning, pouring over seed catalogues and dreaming of the wonderful garden we will have this summer or we can move our gardening indoors and start our seeds off under artificial lights.

Location

Since the set up isn't exactly pretty, you probably won't want it sitting right in the middle of your living room and will most likely have it hidden away somewhere. If you choose to locate your indoor growing system in a cupboard, you should make sure there is enough oxygen circulating in there for the plants to make use of. Poor air circulation will kill off your seedlings for sure. A spare kitchen cupboard which can be accessed easily and which you can ventilate is a good place for your plants since you can improve light reflection by painting the inside white or lining it with some kind of light reflective material.

Set up

Wherever you decide to set up your indoor growing system, there is one important point to remember - cleanliness is the key. In the warm indoors environment pests and diseases will quickly spread so you want your equipment and growing area to be as sterile as possible. Make sure you sterilise all your seed trays and pots and only use new, clean compost.

Your seed trays or pots should sit inside a watertight container. Cover the base of the watertight container with gravel so that the seed trays are not sitting directly in the run off water. It is best to keep a little water in the base tray so that humidity will be retained around the plant.

Choosing the right lights

This is where it all gets really complicated - if you want to make it that way. A simple search on the Internet will present you with a vast array of lights for you to choose from - incandescent plant lights, daylight fluorescents, metal halides, high pressure sodium, combination lights. Some of these lights can be very expensive and, certainly if you decide to grow plants indoors as a serious hobby, you could invest in something more sophisticated. Alternatively, you could make do with two simple fluorescent tubes or a collection of adjustable desk lamps with the light trained onto your seed tray or plants.

Daylight bulbs are designed to mimic the spectrum of light given off by natural sunlight and, if you can get a hold of them, these are good lights to choose. They are available as tubes or as ordinary bulbs. Whatever lights you choose, you should be able to adjust them as the plants grow and they should be located inside a reflective light fitting.

You should place your lights directly over the plants, around four to eight inches away from the top. With fluorescent bulbs, you won't get much heat but make sure you won't damage the plant by placing your hand under the bulb. If you feel it hot, then the plants will too and you should move the light source away a bit. If you're using a fluorescent tube light fitting, you'll need to suspend it on a pulley system that lets you move it up and down.

Controlling the light

Plants need light, that's true, but they also need darkness. How many hours of darkness will depend on the plant but, as a general rule, you should think about the number of hours sunlight there would be if you were growing this plant outdoors. In other words, consider when you would normally sow your seeds outdoors. What would be the number of hours daylight during that time? As the plants mature, you would increase the amount of light accordingly. It's best to have your lights set to a timer switch for this.

Feeding and watering

Since your plants are confined to pots, they can't send out their roots in search of food, so you need to think about feeding them, especially as they get older. Initially, you shouldn't have to fertilise at all because there will be a certain amount of nutrients in the compost. As your seedlings grow, you should feed them a balanced liquid fertiliser. Feeding with a liquid fertiliser ensures that excess food is washed away and there is less chance of the plants becoming over-fertilised. While the plants are still quite small, you should water them with a light water spray so that the seedlings are not damaged and you can add some liquid fertiliser to this spray once a week or so.

General care

Don't be tempted to over water or over feed. Keep a close eye on your plants and they'll tell you when something's wrong. If they start to look sickly, you should consider your watering and feeding regime first. If they are growing 'leggy' - that is, a tall stem with a stunted leaf growth at the top, then you don't have sufficient light and should install more or move the light source closer to the plants.

Pot on your plants when they show signs of outgrowing their space and make sure you handle seedlings by the leaves and not the delicate stems.

Hardening off

If you intend to plant your plants outdoors, the you will have to prepare them for the shock of leaving the nest. Start by moving them to a windowsill which receives direct sunlight if possible. If you don't have one, you will have to bypass this step and begin moving them outdoors. Put them outside during the day and bring them back in at night for a few weeks or until there is no more danger of frost but remember, the plants may be used to more hours of sunlight in your artificial growing system so they might need to be put back under lights for an hour or two when you bring them indoors. Plants respond very much to the length of the day and you'll only confuse them if you suddenly give them eight hours of light when you've been giving them twelve. They will interpret this as a seasonal change and may respond accordingly.

Once you've got them fully hardened off, you can put them outside. Alternatively, you could keep them indoors and, you never know, you might even be enjoying home grown tomatoes next year, in the middle of winter.

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